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Android Android Lists and Adapters (2015) Updating the Data Model Using JSONArray

Posted by Mario Zamora
Mario Zamora
1,396 Points

Why Log.i () method doesn't run ?

hi,

I'm about to accomplish the CodeChallenge for the activity 2 of 2, but when i'm required to write a for loop to add JSONObjects into a JSONArray everything seems to be right however i got an error because the TAG is nos declared correctly. I think i create the for loop succesfully but i don't know why is the TAG the problem.

CodeChallenge.java 
// JSONObject 'jsonData' was loaded from data.json



JSONArray jsonShows = jsonData.getJSONArray("shows");


for(int i=0; i<jsonShows.length(); i++) {


    JSONObject test = jsonShows.getJSONObject(i);


}

  Log.i( TAG , "CodeChallenge"  );
data.json 
{
    "name":"Netflix Playlist",
    "shows":[
        {
            "title":"Doctor Who",
            "season":8,
            "episode":3
        },
        {
            "title":"Arrow",
            "season":1,
            "episode":10
        },
        {
            "title":"Portlandia",
            "season":4,
            "episode":5
        }
    ]
}

4 Answers

Kourosh Raeen
Kourosh Raeen
23,733 Points
Kourosh Raeen
Kourosh Raeen
23,733 Points

Hi Mario - The challenge says to use "CodeChallenge" as the tag so use that string as the first argument of Log.i(). The second argument needs to be the show's title. To get the title call the getString() method on the current JSON object in the loop with the argument "title". Also, the Log.i statement needs to be inside the loop.

Mario Zamora
Mario Zamora
1,396 Points
Mario Zamora
Mario Zamora
1,396 Points

hi Kourosh,

Thank you so much for your help. i add the code according to your previous remark and what i understood:

JSONArray jsonShows = jsonData.getJSONArray("jsonshows");

for (int i=0; i<jsonShows.length(); i++) {

     JSONObject test = jsonShows.getJSONObject(i);
     String  title = test.getString("title");
     Log.i("CodeChallenge" + title);

}

but it throws an error:

Your loop should run three times and call 'get JSONObject()' each time through

Thanks in advance,

Kourosh Raeen
Kourosh Raeen
23,733 Points
Kourosh Raeen
Kourosh Raeen
23,733 Points

The key for the JSONArray is "shows" not "jsonShows":

JSONArray jsonShows = jsonData.getJSONArray("shows");

Also, Log.i needs two argument so instead of concatenating title to the string "CodeChallenge" you need to pass it as the second argument:

Log.i("CodeChallenge", title);
Mario Zamora
Mario Zamora
1,396 Points
Mario Zamora
Mario Zamora
1,396 Points

Thank you so much Kourosh,

I already got my Bagde for completing the module Updating the Data Model. The right code is:

for(int i=0; i<jsonShows.length(); i++){

 JSONObject matrix = jsonShows.getJSONObject(i);
 String title = matrix.getString("title");
 Log.i("CodeChallenge", title);

}

I really appreciate your help

:)